With development of new technologies such as cloud computing, a heat density of an information technology (IT) device becomes larger, and a higher requirement is imposed on a cooling capacity of an air conditioner in an equipment room. However, generally, an IT device is not always operating at full load. If a cooling device still operates at high load when the IT device operates at low load, a waste of energy is inevitable. To improve energy efficiency, an effective measure must be taken, to adjust an operating status of the air conditioner in the equipment room according to a load state of the IT device to implement on-demand cooling, that is, to ensure that a cooling capacity requirement of the IT device is met, ensure stable operating of the IT device, and avoid wasting a cooling capacity and consuming extra energy.
In the conventional art, a temperature sensor configured to detect a return air temperature is installed on a return air vent side of an air conditioner, and the temperature sensor is connected to a controller that controls a fan of the air conditioner.
The controller obtains a return air temperature according to the temperature sensor, and adjusts a rotational speed of a corresponding fan of the air conditioner according to a difference between the return air temperature and a specified value. If the return air temperature is greater than the specified value, the rotational speed of the fan is increased, an air volume is increased, and a cooling capacity is increased. If the return air temperature is less than the specified value, the rotational speed of the fan is reduced, an air volume is reduced, and a cooling capacity is reduced.
However, in an equipment room, an in-room air conditioner is used for cooling. If different IT cabinets have different device load, a temperature difference easily exists in the equipment room. Consequently, return air temperatures detected by temperature sensors are different, further causing different fan rotational speeds of air conditioners and different air pressures. A plenum is disposed on a supply air vent side of the air conditioner. Therefore, air blown by a fan with a high air pressure flows to an area with a low air pressure. As a result, an insufficient air volume is caused in an area under the charge of the fan, load cannot be met, and a hot spot is generated.